title: Over-expression of a Zea mays L. protein phosphatase 2C gene (ZmPP2C) in Arabidopsis thaliana decreases tolerance to salt and drought.
abstract: ZmPP2C (AY621066) is a protein phosphatase type-2c previously isolated from roots of Zea mays (LD9002). In this study, constitutive expression of ZmPP2C in Arabidopsis thaliana under the control of the Cauliflower Mosaic Virus (CaMV) 35S promoter decreased plant tolerance to salt and drought during seed germination and vegetative growth. When growing on media with NaCl or mannitol, the ZmPP2C-overexpressed plants displayed more severe damages, with weaker growth phenotypes corresponding to a series of physiological changes: lower net photosynthesis rate (Pn) and free proline content, higher malondialdehyde (MDA) level, higher relative membrane permeability (RMP), and water loss. Under these stress conditions, they also showed decreased transcription of the stress-related genes RD29A, RD29B, P5CS1, and P5CS2, and ABA-related genes ABI1 and ABI2. Further, the transgenic plants became less sensitive to abscisic acid (ABA). ZmPP2C over-expression significantly attenuated ABA inhibition on seed germination and root growth of the transgenic plants. These results demonstrate that ZmPP2C is involved in plant stress signal transduction, and ZmPP2C gene over-expression in Arabidopsis thaliana may be exploited to study its potential roles in stress-induced signaling pathway.
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, PR China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Liu
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Hu
authors.forename: Jian
authors.initials: J
authors.lastname: Song
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Zong
authors.forename: Dapeng
authors.initials: D
authors.lastname: Li
authors.forename: Dequan
authors.initials: D
authors.lastname: Li
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000222:Adaptation, Physiological / Q000187:drug effects*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics*; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects; D008353:Mannitol / Q000494:pharmacology; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D010788:Photosynthesis / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development; D030821:Plants, Genetically Modified; D000071636:Protein Phosphatase 2C; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D003313:Zea mays / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D008353:Mannitol; D012965:Sodium Chloride; D000040:Abscisic Acid; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C